28021889 has 8 divisors (see below), whose sum is σ = 33417600. Its totient is φ = 22974336.

The previous prime is 28021883. The next prime is 28021897. The reversal of 28021889 is 98812082.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28021889 - 2⁸ = 28021633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28021883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 86864 + ... + 87185.

It is an arithmetic number, because the mean of its divisors is an integer number (4177200).

Almost surely, 2^28021889 is an apocalyptic number.

It is an amenable number.

28021889 is a deficient number, since it is larger than the sum of its proper divisors (5395711).

28021889 is a wasteful number, since it uses less digits than its factorization.

28021889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174079.

The product of its (nonzero) digits is 18432, while the sum is 38.

The square root of 28021889 is about 5293.5705341480. The cubic root of 28021889 is about 303.7380050246.

The spelling of 28021889 in words is "twenty-eight million, twenty-one thousand, eight hundred eighty-nine".